1. Field of the Invention
The invention relates to an article and method for the delivery of nucleic acids or drugs and, in particular, to an article and method for the co-delivery of a nucleic acid and a drug.
2. Discussion of the Related Art
The delivery of DNA to cells is an important aspect of many therapeutic and diagnostic procedures in the fields of medical treatment and research. Methods of delivering DNA to cells are typically divided into viral and non-viral gene delivery systems. In general, viral systems have been more effective at transfecting the DNA to the target cell, while non-viral systems are typically safer and easier to produce. Non-viral delivery methods include liposomal delivery vehicles and peptide-DNA complexes. Also included are mechanical methods, such as microinjection, pressure and particle bombardment. Electrically oriented techniques include electroporation at different voltages. Chemical techniques include the use of DEAE-dextran, calcium phosphate, lipids, proteins, dendrimers and other polymers. (Luo, D. & Saltzman W. M. Synthetic DNA delivery systems. Nature Biotechnol. 18, 33-37 (2000).)
Specific polymers include polyethyleneimine (PEI), polylysene (pLys), and polyamidoamine dendrimers. These materials typically work by condensing DNA in aqueous media and then delivering the DNA to a target such as a cell.
Successful transfection of DNA to a cell can involve more than just delivering the DNA to the cell membrane. The DNA must pass through the cell membrane and be delivered, intact, to the nucleus of the cell in order, for example, to succeed in transferring a vector for the purposes of therapy. Furthermore, this transfection preferably should occur without causing death or damage to the cell that is being treated. Gene therapy and other methods that make use of DNA transfection may be more successful when used in conjunction with a drug that can, for example, help to stabilize the DNA, facilitate delivery of the DNA to the nucleus, or stabilize the cell that is being transfected. Different drugs may also be used in conjunction with gene therapy for the treatment of a specific disorder. For example, both gene therapy and chemotherapy may be useful in treating specific forms of cancer.